Worry more, live longer

Next time the anxiety induced by another gloomy bank balance or the threat of yet more redundancies in your office convinces you that the recession should come with a government health warning, think again.

Dr Marios Kyriazis, a GP and expert in geriatric medicine, is among a growing number of health professionals claiming that stress isn't the one-way road to illness and an early grave that most of us assume. In fact, provided it's relatively short-term, it appears that stress can do wonders for the immune system and ageing process, not to mention keeping the likes of Alzheimer's, arthritis and certain cancers at bay.

"We tend to blame stress for everything from exhaustion to bad moods to heart disease, but it's all a myth. Far from being bad for you, stress is vital for survival. I advise people to seek out stress because it can make you live longer. I actually think the recession – even if it means losing your job – will, for many people, be good for their health. It's people who have routine, uncomplicated, unchallenging lives that tend to be harder hit by ill-health," explains Kyriazis, who is president of the British Longevity Society and author of the book Anti-Ageing Medicines (Watkins).

It's the degree of stress that is crucial. "There's a lot of research and it all points to mild and moderate stress working in the body's favour by increasing the production of regenerative proteins that nourish brain cells, enabling them to function at peak capacity. These cells reinforce the neural connections and physical repair pathways that usually deteriorate with age," he says.

In particular, short-term stress benefits memory function and can even protect against diseases such as Alzheimer's, says Kyriazis. Some research also suggests stress may staunch oestrogen production, thereby helping to prevent breast cancer. Meanwhile, another study found that people who experience moderate levels of stress before surgery had a better recovery than those with high or low levels. Another found children of mothers who had higher levels of the stress hormone cortisol during pregnancy were developmentally ahead of those of women with lower levels.

Research by Texas University even revealed that people who spent most of their lives in undemanding jobs had a 43 per cent risk of dying prematurely – indicating that a regular dose of pressure at work could keep the doctors away.

"If you think about it, all this is entirely logical. If your body is stressed, it is stimulated and therefore continually has its immunological defences tested and provoked, which strengthens it," says Kyriazis.

If you're susceptible to colds, it's definitely time to inject some adrenalin into your life, according to research. A really tight deadline at work or an arduous job interview can trigger hormones that prepare the immune system for danger, as well as improving heart function, both of which help the body fight infections. One study on women showed short bouts of mental or physical activity before getting the flu shot produced more antibodies. "One US scientist put it perfectly, saying that we wouldn't have evolved a fight-or-flight system that allows us to run from the jaws of a lion only to succumb to the jaws of a bacterium," says Doug Carroll, health psychologist at the University of Birmingham.

Carroll and his colleague Anna Phillips, also a health psychologist at the University of Birmingham, have been involved in some of the most recent work around stress and health. "I don't think there's any argument that chronic stress – that is, severe and enduring stress brought on by things like bereavement, long-term unemployment or a bad marriage – is bad for most of the body's systems," says Phillips. "But when it comes to short-term stress, we found the 'stress equals ill health or death' model is more complicated than you might assume."

In their most recent study, participants were asked to do things such as public speaking or sums under a time pressure while being harassed. Interestingly, Carroll and Phillips found that those who showed the greatest cardiovascular response to these acute stress tasks were less likely to become obese, less likely to report depression and crucially more likely to report good health. Phillips emphasises there is no proven causal link, but she'd like to see more research around this.

The general advice on recognising good stress from bad is asking yourself whether you feel a sense of accomplishment or excitement either during or afterwards. A feeling of complete overwhelming, on the other hand, generally points to bad stress. If stress continues longer than 24 hours, it can also start to sour the good benefits of stress.

Phillips is sceptical, though, about whether people's self-perceptions of stress are reliable. "When we get people to do sums under a time pressure, some participants say they found it really stressful and yet we don't find much of a reaction. Others say they felt relatively unstressed and yet their heart rate was up by 20 beats a minute."

It wouldn't be fair to ignore the studies that suggest short-term stress can precipitate acute illness and even sudden death. Increases in admissions to coronary care units and death from heart attacks were recorded after earthquakes hit California, Greece and Japan – and similar effects have also been found during military conflicts. The number of heart attacks treated in Tel Aviv's main coronary care unit in late January 1991, the peak of the Iraqi Scud missile attacks on the city, was almost twice as high as usual.

Then there's football. Yes, really. Between 1995 and 1999, on days when the local professional football team lost at home, relative to days with other match outcomes, death from heart attacks and strokes was found to increase, again by 25 per cent, in men in the North East of England. But, points out Carroll, it is quite possible that all these people already had the risk markers for a heart attack. "The acute stress response could well have been the trigger rather than the cause," he says.

Dr John MacLeod, a GP and reader in clinical epidemiology and primary care at Bristol University, is certainly unconvinced there is a proven link with stress. One of his studies – of 5,600 men in 27 workplaces in Scotland – found a lower incidence of heart disease and death overall in those most likely to say their lives were stressful.